| 摘要 |
Defoaming and deaerating mixtures based on oil-in-water emulsions where the oil phase comprises from 5 to 75% by weight of the emulsion for aqueous media prone to foaming, wherein the oil phase comprises a) at least one alcohol having at least 12 carbon atoms, distillation residues obtainable in the course of the production of alcohols having a higher carbon number by the oxo process or by the Ziegler process, or mixtures thereof, b) at least one ester of a sugar alcohol having at least 4 OH groups or at least 2 OH groups and at least one intramolecular ether bond and a fatty acid having at least 20 carbon atoms in a molar ratio of 1:at least 1, in which case the free OH groups of these esters are optionally wholly or partly esterified with C12-C18-carboxylic acids, and optionally c) fatty acid esters of alcohols having at least 22 carbon atoms and C1-C36-carboxylic acids, fatty acid esters of C12-C22-carboxylic acids and monohydric, dihydric or trihydric C1-C20-alcohols, polyethylene waxes, natural waxes or mixtures thereof, and optionally d) hydrocarbons having a boiling point above 200 DEG C., fatty acids having from 12 to 22 carbon atoms, or mixtures thereof are useful for foam control in relation to aqueous media prone to foaming, in particular for foam control in pulp cooking, pulp washing, the beating of paper stock, papermaking and the dispersing of pigments for papermaking.
|
